JP3055976B2 - Manipulator device with torque supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manipulator device having a torque supply device and a torque supply method therefor. The present invention relates to a manipulator system.

[0002]

2. Description of the Related Art A conventional apparatus is disclosed, for example, in Japanese Patent Publication No. 3-308.
As described in Japanese Patent Publication No. 32, a torque detector for detecting a tightening torque to a screw tightening device, an electric screwdriver for preventing the inertial force of a rotating body such as an electromagnetic clutch from being transmitted to a screw at the time of screw tightening. It consists of three elements: a circuit and a timed circuit that detects the timing immediately before the screw contacts the pedestal. On the other hand, 3-3
Japanese Patent Application Publication No. 0833 describes the same device as described above in which the driving source is an induction motor.

[0003]

Since the conventional apparatus focuses only on the torque supply mechanism, it is necessary to cope with the case where a plurality of torque receiving ports are scattered, and particularly, to adjust the attitude of these torque receiving ports to the torque supplying mechanism. There was no means for handling different cases for different devices. In addition, with the conventional torque supply device, starting from the point when the screw is inserted into the screw hole, it is rotated at a high speed for a certain period of time to reduce the working time during that time. In this case, it is intended to accurately manage the torque at the time. Therefore, it is premised that the bit (driver tip) of the screw tightening device is correctly fitted to the screw and that the screw is correctly inserted into the screw hole.

FIG. 10 is a perspective view of a general manipulator torque supply device. In a manipulator 900 as shown in FIG. 10, when torque is transmitted to the object 920 by the torque transmission device of the end effector 910 attached to the tip, the torque driver 911 is correctly fitted to the screw head 921 of the object from the beginning. Not limited to this, the screw provided on the screw head,
It doesn't always fit right into its counterpart threaded hole. Therefore, when the screw is tightened by the conventional technique, the timing of switching from the high speed to the low speed changes every time the screw is tightened, and the operation becomes ineffective.

In the prior art, the screw tightening time is measured in advance, and the switching timing from the high speed to the low speed is set based on the measured time. Or when the load torque fluctuates and the rotational speed of screw tightening changes, there is a problem that its effectiveness cannot be exhibited. Further, in the prior art, no consideration has been given to measures to be taken when a bit and a screw or a screw and a screw hole do not properly fit and cause idling or galling.

[0006]

An object of the present invention is to solve the above-mentioned problems of the prior art.
It was made to determine the
Therefore, when there is play or idle rotation for initial coupling between the torque supply unit and the torque reception unit of the object, torque transmission,
Alternatively, torque transmission when there is a possibility of galling during torque transmission can be performed automatically and remotely.
An object of the present invention is to provide a manipulator device with a torque supply device .

Another object of the present invention is to make it possible to correctly perform an initial connection between a screw and a screw hole, for example, in the case of screw tightening, so that the screw tightening operation can be efficiently performed and the screw tightening operation can be efficiently performed. An object of the present invention is to provide a manipulator device with a torque supply device that can prevent a failure such as damage to a screw portion caused by galling between a screw and a screw hole due to an appropriate initial connection.

Still another object of the present invention is to provide a method for gripping a work tool with an end effector and driving the work tool with the torque of a torque supply device, thereby enabling reliable transmission of torque and removal of the tool. There is no need to provide means for judging pass / fail, and the manipulator with a torque supply device has a small and lightweight end effector and tool.
Data device .

[0010]

Means for Solving the Problems] To achieve the above object, the present invention includes a plurality of manipulators arms, and drive means for driving the respective joints, the plurality of manipulators
An end effector attached to the distal end of the arm, and a manipulator device having control means for controlling each of the driving means, at least a torque supply drive motor, an encoder for detecting the rotation angle of the motor, slip for extracting a transmission for shifting a rotational speed, is connected to an output shaft of the speed change device, pairs elephants was detected by the torque sensor and said torque sensor for detecting a torque received upon transmitting torque to the torque signal A torque supply unit configured to include a ring and a shoe, and a torque supply unit configured to be inserted into a torque reception unit of the object and to supply a torque output of the speed reducer to the end effector. A manipulator device with a torque supply device, wherein the manipulator device is provided. Further, the present invention has a plurality of manipulator arms, a driving unit for driving each joint thereof, an end effector attached to a distal end of the plurality of manipulator arms, and a control unit for controlling each of the driving units. In the manipulator device, at least a torque supply drive motor, an encoder for detecting a rotation angle of the motor, a transmission for changing the number of rotations of the motor, and a torque receiving / receiving object connected to an output shaft of the transmission. A torque supply unit that supplies a torque output of the speed reducer by inserting the torque supply unit into the unit, and guides the torque supply unit when the torque supply unit is inserted into the torque reception unit, provided around the torque supply unit; A guide means provided at a lower portion with a strain gauge for detecting a strain corresponding to a torque reaction force received when the torque supply unit transmits torque to the object; A torque supply device including a plurality of side distance sensors that measure a distance between the torque supply unit and the object so that the inclination of the torque supply unit with respect to the object can be detected. A manipulator device with a torque supply device, wherein the manipulator device is provided.

[0011]

Further , the present invention provides the above-mentioned torque supply device.
In the manipulator device, the torque supply device
Furthermore, the inclination of the torque supply unit with respect to the object is
The distance between the object and the object so that it can be detected.
It is characterized by comprising a plurality of distance measuring sensors for measuring.
In addition, the present invention provides a method for controlling each joint of a plurality of manipulator arms.
Drive the end effector at the tip of the manipulator.
Manipulators that operate in close proximity to or coupled to an object
In the end effector, the end effector has at least
Also drive the torque supply drive motor and change the rotation speed of the motor
And a transmission connected to an output shaft of the transmission,
The torque output of the reduction gear
The distance between the torque supply unit to be supplied and the object is measured.
And a plurality of distance measuring sensors for measuring the torque.
And a torque supply unit for receiving the torque.
At the time of initial connection close to the feed unit, each of the distance measuring sensors
The torque supply unit based on each distance to an object to be measured.
Angle of inclination of the
Driving each joint of the manipulator arm to adjust the posture of the tip
Tor with a control means for controlling correctly
This is a manipulator device with a supply device .

[0013]

According to the above construction, by using a plurality of distance measuring sensors, the inclination angle of the torque supply unit is obtained when the torque supply unit approaches the torque reception unit for initial coupling, and when there is an inclination, the manipulator arm is used. The posture of the tip of the can be controlled correctly.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. Embodiment 1 First, FIG. 1 is a perspective view of an end effector portion and an object of a manipulator according to an embodiment of the present invention. In FIG. 1, reference numeral 910 denotes an end effector having a torque supply device, and a manipulator 900.
It is attached to the tip. The end effector 910 grips the torque receiving units 920, 930, and 940, transmits torque to the torque receiving units 920, 930, and 940 by a torque supply device built in the end effector 910, and Thereby, the object 950 can be attached to the structure 960. Note that the end effector 910 and the torque receiving units 920, 9
For example, as a coupling mechanism with the first and second horns 30 and 940,
-169121. Also,
As a coupling means of the torque receiving units 920, 930, and 940, for example, U-21-89-23 proposed by the present inventors can be used.
25 can be realized.

Next, an embodiment of the torque supply device in the above-mentioned manipulator will be described. [Embodiment 2] FIG. 2 is a schematic diagram showing an example of a torque supply device in the manipulator of FIG. 2, reference numeral 100 denotes a torque supply device main body, which includes a driving motor 101, an encoder 102, a speed reducer 103, a torque supply unit 104, and a guide 110. Motor 10
The first power is reduced or increased in speed by the speed reducer 103 to a required torque and rotation speed, and transmitted to the torque supply unit 104. The torque supply section 104 can tighten or loosen a screw by using a driver bit, and can supply torque to various objects by using any other structure. .

The encoder 102 detects the rotation angle of the motor 101, and calculates the number of rotations of the torque supply unit 104 by multiplying the speed ratio of the speed reducer 103. The encoder 102 may be installed on the output shaft side of the speed reducer 103 so that the rotational speed of the torque supply unit 104 can be directly detected. When the rotation speed needs to be detected, the rotation speed can be obtained by differentiating the encoder signal 105. Guide 110
When the torque supply device main body 100 is inserted into an object to which torque is to be supplied, mutual alignment is taken.
Further, it is for receiving a torque reaction force when supplying torque.

The transmission torque is obtained by detecting the motor drive current 106 and using the following equation.

[Equation 1] t = K · i · s · η (Equation 1) where t: Transfer torque K: Motor torque constant i: Motor drive current s: Speed ratio of reduction gear η: Mechanical transmission of reduction gear efficiency

[Embodiment 3] FIG. 3 is a schematic structural view of a torque supply device according to another embodiment of the present invention. In the figure, those having the same reference numerals as those in FIG. 2 are the same as those in the embodiment of FIG.
That is, in the embodiment of FIG. 3, the torque supply unit is provided with a torque sensor. The point that the torque supply device main body 200 includes a motor 101, an encoder 102, a speed reducer 103, a torque supply unit 104, and a guide 110 is the same as FIG.
This is the same as the embodiment shown in FIG. The difference from FIG. 1 lies in that a torque sensor 120, a slip ring 121, and a shoe 122 are added to the output shaft side of the speed reducer 103.

The power of the motor 101 is transmitted to the torque transmitting section at a required torque and rotation speed by the speed reducer 103, and the magnitude of the torque is detected by a torque sensor 120. As the torque sensor 120, means for detecting the torsion of the shaft with a strain gauge or the like is used. However, since the torque sensor 120 itself rotates, a signal is taken out by the slip ring 121 and the shoe 122 and detected as a torque signal 123.

[Embodiment 4] Next, another embodiment for detecting a transmission torque will be described with reference to FIG. FIG. 4 is a schematic configuration diagram of a torque supply device according to another embodiment of the present invention. In the figure, those having the same reference numerals as those in FIG. 2 are the same as those in the embodiment of FIG. The torque supply device 300 includes the motor 10
1, encoder 102, reduction gear 103, torque supply unit 1
4 and the guide 110 are the same as the embodiment shown in FIG. The difference from FIG.
The difference is that a strain gauge 130 is attached to the base of No. 10 and a relief 131 is provided around the strain gauge 130.

As described above, the guide 110 receives a torque reaction force when the torque supply unit 104 transmits torque to an object. At this time, the guide 110 is deformed by the torque reaction force, and the deformation is detected by the strain gauge 130. The output of the strain gauge 130 and the torque supply unit 1
04, that is, the reaction torque received by the guide 110, a constant relationship is established. Therefore, it is necessary to know the torque value and the output 132 of the strain gauge 130 in advance to obtain the torque value of the torque supply unit 104. Can be.
When the torque supply device 300 comes into contact with an object to be supplied with torque, the escape portion 131 provided at the base of the guide 110 is used by the joint of the object and the strain gauge 13.
This is to prevent 0 from being damaged.

Next, an embodiment in which torque transmission is performed using each of the above-described torque supply devices will be described. FIG. 5 is a diagram showing the relationship between the rotation speed and the torque in the case of screw tightening, and FIG. 6 is a flowchart showing an algorithm when the torque supply is automated. First, FIG. 5 shows the relationship between the number of rotations of the torque supply unit and the screw tightening torque when screw tightening is performed by each of the torque supply devices. If the torque supply unit is properly fitted into the screw and the screw is properly fitted into the screw hole, screw tightening starts from point A in FIG. At this point, the specified torque t is reached. However, if the torque supply unit is not correctly fitted to the screw, or if the screw is not properly fitted to the screw hole, the specified torque t will not be obtained even at the specified rotation speed n (point E), that is, idling may occur. If the specified torque t is exceeded before reaching the specified number of revolutions (point D), that is, the galling of the screw may occur.

Table 1 shows a method for judging the tightening state of the screw by the above means from the detection signals of the number of revolutions and the torque.

[Table 1] The tightening state of the screw can be determined based on two detection signals of the number of rotations and the tightening torque from the start of the screw tightening operation of the torque supply device.

Next, with reference to FIG. 6, an embodiment of automatically supplying torque using the above-described torque supply device and the method for determining the torque transmission state (Table 1) will be described. FIG.
In step No. Is written in parentheses. As shown in FIG. 6, the screws are tightened (step 10), and it is determined whether or not the current rotational speed n has reached the specified rotational speed N (step 11). If not, it is determined whether or not the current tightening torque t has reached the specified torque T (step 13). If not reached, return to step 10 and continue screw tightening. If the specified torque has been reached in step 13, the screw is galling,
The reverse operation is performed once (step 15), and the process returns to step 10 again to repeat the operation. If the number of revolutions has reached the specified number of revolutions in step 11, it is determined whether the current tightening torque t has reached the specified torque T (step 1).
2). If it has reached the end of the work.

If the torque has not reached the specified torque in step 12, the screw is running idle, so the reverse operation is performed once (step 17), and the screw tightening operation is performed again (step 18). This operation is repeated until the tightening torque reaches a specified value. In these operation processes, an appropriate upper limit number M, M 'is set for the number of repetitions m, m' of a series of operations for performing normal rotation after performing reverse rotation for idling or galling. Prevent time from unnecessarily increasing. The number of repetitions is M, M
In the case where the value of 'has been reached, an alarm is issued to inform the operator, and a measure such as removing a defect by manual operation is performed.

Next, with reference to FIGS. 7 and 8, a description will be given of a method of detecting a tightening state of a screw using a distance measuring sensor. [Embodiment 5] FIG. 7 is a side view of a screw fastening device having a distance measuring sensor according to still another embodiment of the present invention. The screw tightening device 400 has the same configuration as the torque supply device shown in FIGS. 2 to 4, and a screwdriver bit 401 suitable for the screw 420 is attached to the tip of the screw tightening device 400. . A distance measuring sensor 410 is attached to the screw tightening device 400,
The distance to the object 440 to which the screw 420 is tightened can be measured.

FIG. 7A shows a state in which the screw 420 has entered the screw hole 430. Here, the following equation holds.

L = a + b (Equation 2) where l: distance from the distance measuring sensor 410 to the object a: length under the neck of the screw 420 b: length from the distance measuring sensor 410 to the bearing surface of the screw 420

Next, FIG. 7B shows a state in which the screw 420 is completely tightened. At this time, the following equation holds.

L ′ = b (Equation 3) where l ′ is the distance from the distance measuring sensor 410 to the object. That is, the distance from the distance measuring sensor 410 to the object is
When the value of b is reached, screw tightening is completed. Note that b is obtained in advance from [Equation 2].

Next, with reference to FIG. 8, a description will be given of a method of detecting the tightening state of the screw using a plurality of distance measuring sensors and correctly fitting the screw into the screw hole. [Embodiment 6] Fig. 8 is a side view of a screw fastening device having a distance measuring sensor according to still another embodiment of the present invention. 8, the screw tightening device 400A is similar to FIG.
4 is similar to the torque supply device shown in FIG. 4 and has a driver bit 401 at the end thereof. The screw fastening device 400A includes two distance measuring sensors 410 and 41.
1 is attached, and when the distance measuring sensors 410 and 411 and the object 440 are about to have the center line coincident with the screw hole 430 at the angle θ, the following equation is established.

[0030]

(Equation 4) Here, θ: angle formed by the center line of screw 420 with respect to the center line of screw hole 430 Δl = l′−l l ′: distance between distance measuring sensor 410 and object 440 l: distance measuring sensor 411 and object 440 C: In the distance between the axes of the distance measuring sensors 410 and 411 (Equation 4), Δl and C are given, so that θ can be obtained. By attaching three or more distance measuring sensors, it is possible to detect angles in two directions with respect to the target surface.

Next, a method of aligning the screw with the central axis of the screw hole from the aforementioned θ will be described with reference to FIG. [Embodiment 7] FIG. 9 is an explanatory view in which the screw fastening device of FIG. 8 is applied to a manipulator. In FIG. 9, 400
A is a screw fastening device, which is the same as that shown in FIG. This screw fastening device 400A is attached to the tip of a manipulator 500 having six degrees of freedom. The manipulator 500 is operated by a management computer 510, an arm control device 520, and an arm drive device 530. Now, if the screw is oblique to the screw hole,
As described with reference to FIG. 8, each distance measuring sensor 410,
The distance from the object 440 to the object 440 is the distance signal 412.
Is input to the management computer 510.

In the management computer 510, the inclination of the screw with respect to the screw hole, that is, the angle θ at which the screw tightening device 400A should be tilted in order to correctly fit the screw into the screw hole is calculated by (Equation 4). In addition, the management computer 510 sends this information to the arm control device 520 as a tip posture change command of the manipulator 500. Arm control device 52
At 0, the control amount of each manipulator joint is calculated based on the change amount of the manipulator tip posture, and is input to the arm driving device 530. Therefore, the arm drive device 530 converts the control signal into a voltage or a current for driving each joint motor, and drives each joint of the manipulator 500 as the arm drive signal 501. Manipulator 50
By performing the above-described feedback control during the movement of the tip of the zero, the screw can be accurately fitted into the screw hole. The algorithm for automatic screw tightening shown in FIG. 6 is executed by the management computer 510.

[0033]

[0034]

As described in detail above, according to the present invention,
If the screw is tightened , the torque transmission state can be grasped , that is, the torque transmission when there is play for idling or idle rotation between the torque supply unit and the torque reception unit. Alternatively, there is an effect that torque transmission in a case where galling may occur during torque transmission can be performed automatically and remotely.

Further, according to the present invention, in the case of screw tightening or the like,
In, for example , the initial connection between the screw and the screw hole can be correctly performed, and the screw tightening operation can be performed efficiently, and the screw portion caused by galling between the screw and the screw hole due to inappropriate initial connection can be performed. There is an effect that defects such as damage can be prevented.

Further, according to the present invention, holds the working tool at the end effector, when driving the working tool by a torque of the torque supply apparatus, it is possible to ensure torque transmission, determining the acceptability of the tool mounting Therefore, the end effector and the tool can be reduced in size and weight.

[Brief description of the drawings]

FIG. 1 is a perspective view of an end effector unit and an object of a manipulator according to one embodiment of the present invention.

FIG. 2 is a schematic configuration diagram illustrating an example of a torque supply device in the manipulator of FIG. 1;

FIG. 3 is a schematic configuration diagram of a torque supply device according to another embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a torque supply device according to another embodiment of the present invention.

FIG. 5 is a diagram showing a relationship between a rotation speed and a torque in the case of screw tightening.

FIG. 6 is a flowchart showing an algorithm when torque supply is automated.

FIG. 7 is a side view of a screw fastening device having a distance measuring sensor according to still another embodiment of the present invention.

FIG. 8 is a side view of a screw fastening device having a distance measuring sensor according to still another embodiment of the present invention.

9 is an explanatory diagram in which the screw tightening device of FIG. 8 is applied to a manipulator.

FIG. 10 is a perspective view of a general manipulator torque supply device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Motor 102 Encoder 103 Reduction gear 104 Torque supply part 110 Guide 120 Torque sensor 121 Slip ring 122 Shoe 130 Strain gauge 131 Relief part 400, 401A Screw device 401 Driver bit 410, 411 Distance measuring sensor 440, 950 Object 500, 900 Manipulator 510 Management computer 520 Arm control device 530 Arm drive device 910 End effector 920, 930, 940 Torque receiving unit

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B23P 19/06 B25J 19/00

Claims (4)

(57) [Claims] 1. A plurality of manipulators arms, and drive means for driving the respective joints, the plurality of manipulators A
A manipulator apparatus having an end effector attached to the distal end of the over arm, and control means for controlling the respective driving means, at least, an encoder for detecting a torque feed drive motor, the rotation angle of the motor, the motor of the transmission that the transmission of the rotational speed, is connected to an output shaft of the speed change device, Target was to torque for taking a torque signal detected by the torque sensor and said torque sensor for detecting a torque received upon transmission A torque supply unit comprising: a slip ring and a shoe; and a torque supply unit configured to be inserted into a torque reception unit of the object to supply a torque output of the speed reducer. A manipulator device provided with a torque supply device. [2 Claim: a plurality of manipulators arms, and drive means for driving the respective joints, the plurality of manipulators A
An end effector attached to the tip of the arm, and a manipulator device having control means for controlling each of the driving means, at least a torque supply driving motor, an encoder for detecting a rotation angle of the motor, and the motor of the transmission that the transmission of the rotational speed, is connected to an output shaft of the speed change device, pairs and torque supply unit for supplying the torque output of the speed reducer is inserted into the torque receiving portion of the elephant was of the torque supply unit It is provided around and guides the torque supply unit when the torque supply unit is inserted into the torque reception unit, and detects distortion corresponding to a torque reaction force received when the torque supply unit transmits torque to the object. and guide means provided on the lower a strain gauge that, before
The inclination of the torque supply unit with respect to the object is detected.
To measure the distance to the object so that
A manipulator device with a torque supply device, wherein a torque supply device including a plurality of side distance sensors is provided in the end ejector. 3. The torque supply device further includes a plurality of side distance sensors for measuring a distance between the torque supply unit and the object so that an inclination of the torque supply unit with respect to the object can be detected. torque supply device with a manipulator device according to claim 1 Symbol mounting, characterized in that. 4. A manipulator device for driving each joint of a plurality of manipulator arms to operate an end effector at a tip end of the manipulator close to or coupled to an object, wherein the end effector includes at least a torque supply drive motor and A transmission that changes the rotational speed of the motor, a torque supply unit that is connected to an output shaft of the transmission, and that is inserted into a torque receiving unit of the object to supply a torque output of the speed reducer; A torque supply device configured to include a plurality of side distance sensors for measuring a distance to an object; and further, when the torque supply unit is initially coupled close to the torque reception unit, each of the side distance sensors is provided. The inclination angle of the torque supply unit is obtained based on each distance between the object and the object measured by the sensor, and the manipulator arm is operated in accordance with the obtained inclination angle. Torque supply device with a manipulator device characterized by comprising a control means for controlling correct the attitude of the distal end portion by driving the joints.